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  • 1
    ISSN: 1460-9568
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The antiepileptic drug lamotrigine was described to exert its effects on neuronal excitability via voltage-gated sodium and calcium, as well as hyperpolarization-activated conductances. In order to define the effects of lamotrigine on the excitability of layer V pyramidal cells of the rat somatosensory cortex we performed patch-clamp recordings from the soma and dendrite of this major cortical output cell type in acute slices. Voltage-clamp experiments revealed the blockade of the persistent sodium current by 50–100 µm lamotrigine as well as by 50 µm of the anticonvulsant drug phenytoin. In somatic current-clamp studies lamotrigine, in a therapeutic concentration range, depolarizes the membrane potential reflecting the activation of the hyperpolarization-activated current. This depolarization reduces the rheobase and increases the spiking frequency at the onset of the spike train. For long depolarizing current pulses under lamotrigine, however, a use-dependent block of sodium channels reduces spiking frequency and spike amplitude. The depolarization due to 50–100 µm lamotrigine reduces additionally the critical frequency of back-propagating spikes necessary to elicit a dendritic calcium action potential. Ten to thirty micromolar lamotrigine, in contrast, did not change the critical frequency. Lamotrigine blocks long-lasting, high frequent spiking activity due to its use-dependent sodium channel block, while burst activity is not impaired due to a depolarizing shift of the membrane potential. This drug therefore dampens epileptic activity while leaving the somatodendritic association in layer V pyramidal cells intact.
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  • 2
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background  Recent studies of antidandruff shampoos or tonics containing antifungal or antibacterial agents produced effects suggestive of a potential hair growth benefit.Objectives  The purpose of this 6-month, 200-patient, randomized, investigator-blinded, parallel-group clinical study was to assess the hair growth benefits of a 1% pyrithione zinc shampoo. The efficacy of a 1% pyrithione zinc shampoo (used daily), was compared with that of a 5% minoxidil topical solution (applied twice daily), a placebo shampoo and a combination of the 1% pyrithione zinc shampoo and the 5% minoxidil topical solution.Methods  Two hundred healthy men between the ages of 18 and 49 years (inclusive) exhibiting Hamilton–Norwood type III vertex or type IV baldness were enrolled. Total hair counts, the primary efficacy measure, were obtained using fibre-optic microscopy and a computer-assisted, manual hair count method. Secondary measures of efficacy included assessments of hair diameter, as well as patient and investigator global assessments of improvement in hair growth. These were based on photographs of the scalp using both midline and vertex views.Results  Hair count results showed a significant (P 〈 0·05) net increase in total visible hair counts for the 1% pyrithione zinc shampoo, the 5% minoxidil topical solution, and the combination treatment groups relative to the placebo shampoo after 9 weeks of treatment. The relative increase in hair count for the 1% pyrithione zinc shampoo was slightly less than half that for the minoxidil topical solution and was essentially maintained throughout the 26-week treatment period. No advantage was seen in using both the 5% minoxidil topical solution and the 1% pyrithione zinc shampoo. A small increase in hair diameter was observed for the minoxidil-containing treatment groups at week 17. Assessments of global improvements by the patients and investigator generally showed the benefit of 5% minoxidil. The benefit of the 1% pyrithione zinc shampoo used alone tended (P 〈 0·1) to be apparent only to the investigator.Conclusions  Hair count results show a modest and sustained improvement in hair growth with daily use of a 1% pyrithione zinc shampoo over a 26-week treatment period.
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  • 3
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background Acne is a common skin disorder, but epidemiological data from the general population obtained by examination are scarce. Clinical experience suggests an association between smoking and acne, although confirmatory evidence from appropriate studies is lacking.Objectives To determine the prevalence and demographic factors of acne in a general population sample and to investigate the association of smoking and acne on a qualitative and quantitative level.Methods In a cross-sectional study, 896 citizens (aged 1–87 years, median 42) of the City of Hamburg were dermatologically examined. The prevalence and severity of acne were recorded and further information on demographic variables, medical history, and alcohol and cigarette consumption were obtained by a standardized interview.Results According to the clinical examination, acne was present in 26·8% overall, and was more prevalent in men (29·9%) than women (23·7%) (odds ratio, OR 1·37, 95% confidence interval, CI 1·01–1·87). Prevalence followed a significant linear trend over age with peak prevalence between 14 and 29 years (P 〈 0·001). The reported age at onset was significantly lower in women than men (P = 0·015). According to multiple logistic regression analyses acne prevalence was significantly higher in active smokers (40·8%, OR 2·04, 95% CI 1·40–2·99) as compared with non-smokers (25·2%). A significant linear relationship between acne prevalence and number of cigarettes smoked daily was obtained (trend test: P 〈 0·0001). In addition, a significant dose-dependent relationship between acne severity and daily cigarette consumption was shown by linear regression analysis (P = 0·001).Conclusions Smoking is a clinically important contributory factor to acne prevalence and severity.
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  • 4
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The sodium-vitamin C co-transporter SVCT2 is primarily responsible for the accumulation of the important antioxidant ascorbate into brain cells. In vitro studies have demonstrated strong expression of this transporter in cultured astrocytes, whereas in situ hybridization analysis has so far detected SVCT2 only in neurons. In the present study, we examined the response of SVCT2 mRNA expression in the brain to focal ischemia induced for 2 h by unilateral middle cerebral artery occlusion. The mRNA expression patterns of SVCT2 and the glutamate-activated immediate early gene Arc were investigated at 2 and 22 h after ischemia. SVCT2 and Arc mRNA expression was lost in the ischemic core at both time points. In areas outside the core, Arc was strongly up-regulated, primarily at 2 h, whereas SVCT2 showed an increase at 2 and 22 h. SVCT2 expression was increased in neurons as well as in astrocytes, providing the first evidence for SVCT2 expression in astrocytes in situ. These findings underscore the importance of ascorbate as a neuroprotective agent and may have implications for therapeutic strategies. In addition, the increase of SVCT2 in astrocytes after ischemia suggests that cultured astrocytes are exposed to chronic oxidative stress.
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  • 5
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: We investigated levels and compositions of N-acylethanolamines (NAEs) and their precursors, N-acyl phosphatidylethanolamines (N-acyl PEs), in a rat stroke model applying striatal microdialysis for glutamate assay. Rats (n = 18) were treated with either intravenous saline (control), NMDA receptor antagonist MK801 (1 mg/kg), or CB1 receptor antagonist SR141716A (1 mg/kg) 30 min after permanent middle cerebral artery occlusion (MCAO). MK801 significantly attenuated the release of glutamate in the infarcted striatum (79 ± 22 μmol/L) as compared with controls (322 ± 104 μmol/L). The administration of CB1 antagonist SR141716A had no statistically significant effect on glutamate release (340 ± 89 μmol/L), but reduced infarct volume at 5 h after MCAO significantly by approximately 40%, whereas MK801 treatment resulted in a non-significant (18%) reduction of infarct volume. In controls, striatal and cortical NAE concentrations were about 30-fold higher in the infarcted than in the non-infarcted hemisphere, whereas ipsilateral N-acyl phosphatidylethanolamine (N-acyl PE) levels exceeded contralateral levels by only a factor of two to three. Treatment with MK801 or SR141716A, or glutamate release in the infarcted tissue, had no significant effect on these levels. NAE accumulation during acute stroke may be due to increased synthesis as well as decreased degradation, possibly by inhibition of fatty acid amide hydrolase (FAAH).
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  • 6
    ISSN: 1460-9592
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background The recently introduced TOSCA monitor (Linde Medical Sensors AG, Basel, Switzerland) combines pulse oximetry (SpO2) and transcutaneous PCO2 (PtcCO2) monitoring in a single ear sensor. The aim of the present study was to evaluate accuracy of the TOSCA monitor to estimate SaO2 and PaCO2 in anaesthetized children.Methods With approval of the hospital ethical committee and after obtaining informed parental consent, the TOSCA sensor was attached to one ear lobe of anaesthetized children in whom arterial access was established for cardiac catheterization or invasive blood pressure monitoring. SpO〈inlineGraphic alt="inline image" href="urn:x-wiley:11555645:PAN1146:PAN_1146_mu1" location="equation/PAN_1146_mu1.gif"/〉 and PtcCO2 as well as SpO〈inlineGraphic alt="inline image" href="urn:x-wiley:11555645:PAN1146:PAN_1146_mu2" location="equation/PAN_1146_mu2.gif"/〉 and PECO2 values from the anaesthesia monitoring (AS5; Datex-Ohmeda, Helsinki, Finland) were compared with SaO2 and PaCO2 values from arterial blood gas analysis. Corresponding data were compared using Bland Altman bias analysis.Results A total of 111 blood samples were taken from 60 children (median age: 4.41 years; 0.35–16.13 years). SaO2 values ranged from 63 to 100% (median: 98.7%), PaCO2 ranged from 3.8 to 7.3 kPa (median: 4.6 kPa). Mean difference (±2 sd) between PaCO2 and PtcCO2 was –0.035 kPa (±0.74 kPa), between PaCO2 and PECO2 0.002 kPa (0.73 kPa), respectively (1 kPa = 7.3 mmHg). Bias and precision between SaO2 and SpO〈inlineGraphic alt="inline image" href="urn:x-wiley:11555645:PAN1146:PAN_1146_mu3" location="equation/PAN_1146_mu3.gif"/〉 was –0.63% (±2.77%) and 0.13% (±4.52%) between SaO2 and SpO〈inlineGraphic alt="inline image" href="urn:x-wiley:11555645:PAN1146:PAN_1146_mu4" location="equation/PAN_1146_mu4.gif"/〉.Conclusions In anaesthetized children, the TOSCA ear sensor allows estimation of SaO2 and PaCO2, comparable in accuracy to endtidal capnometry and finger pulse oximetry. This makes the TOSCA monitor a helpful add-on to respiratory monitoring in anaesthetized children, in situations, in which endtidal capnometry is unreliable or difficult to establish.
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  • 7
    ISSN: 1460-9592
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: A congenital laryngotracheo-oesophageal cleft is a rare airway malformation which results from incomplete separation of the larynx and trachea from the hypopharynx and oesophagus. Patients usually present with stridor, aspiration and cyanosis associated with feeding. For early diagnosis, a high index of suspicion is needed. Unless an appropriate diagnostic approach is taken, the diagnosis can be missed. The successful ventilation of a neonate with the Laryngeal Mask AirwayTM is described.
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  • 8
    ISSN: 1365-2486
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
    Notes: We present the annual patterns of net ecosystem-atmosphere exchange (NEE) of CO2 and H2O observed from a 447 m tall tower sited within a mixed forest in northern Wisconsin, USA. The methodology for determining NEE from eddy-covariance flux measurements at 30, 122 and 396 m above the ground, and from CO2 mixing ratio measurements at 11, 30, 76, 122, 244 and 396 m is described. The annual cycle of CO2 mixing ratio in the atmospheric boundary layer (ABL) is also discussed, and the influences of local NEE and large-scale advection are estimated. During 1997 gross ecosystem productivity (947−18 g C m−2 yr−1), approximately balanced total ecosystem respiration (963±19 g C m−2 yr−1), and NEE of CO2 was close to zero (16±19 g C m−2 yr−1 emitted into the atmosphere). The error bars represent the standard error of the cumulative daily NEE values. Systematic errors are also assessed. The identified systematic uncertainties in NEE of CO2 are less than 60 g C m−2 yr−1. The seasonal pattern of NEE of CO2 was highly correlated with leaf-out and leaf-fall, and soil thaw and freeze, and was similar to purely deciduous forest sites. The mean daily NEE of CO2 during the growing season (June through August) was −1.3 g C m−2 day−1, smaller than has been reported for other deciduous forest sites. NEE of water vapor largely followed the seasonal pattern of NEE of CO2, with a lag in the spring when water vapor fluxes increased before CO2 uptake. In general, the Bowen ratios were high during the dormant seasons and low during the growing season. Evapotranspiration normalized by potential evapotranspiration showed the opposite pattern. The seasonal course of the CO2 mixing ratio in the ABL at the tower led the seasonal pattern of NEE of CO2 in time: in spring, CO2 mixing ratios began to decrease prior to the onset of daily net uptake of CO2 by the forest, and in fall mixing ratios began to increase before the forest became a net source for CO2 to the atmosphere. Transport as well as local NEE of CO2 are shown to be important components of the ABL CO2 budget at all times of the year.
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Haemophilia 8 (2002), S. 0 
    ISSN: 1365-2516
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Summary.  Scarce resources in healthcare are a fact of life everywhere. Providing optimal healthcare for haemophilia means delivering the best possible clinical outcomes at an acceptable total cost, however that is defined by individual societies. Health economics helps us to do this. So far, economic evaluation has enhanced our understanding of some of the economic implications of haemophilia and has provided some guidance on the way forward to optimize efficient allocation of resources for this condition. Further advances and consensus on evaluation methods and standards for the economics of haemophilia are required, however. This need will continue in the face of new, more sophisticated and therefore more costly haemophilia therapies.
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  • 10
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: 1. Quantitative aspects of the mating and reproductive biology of the freshwater planktonic calanoid copepod Eudiaptomus gracilis, including duration and frequency of mating, duration of various phases of the oviducal cycle, egg production rate and adult longevity were studied under laboratory conditions. One set of copepods was fed the alga Chlamydomonas reinhardtii whose density was adjusted to 2 × 105 cells mL−1 (about 10 mg C L−1), another set was fed a mixed diet consisting of natural plankton (copepod nauplii, small rotifers and large algae) in the size range of 50–150 μm (dry mass approximately 90 mg L−1).2. The entire mating process, from the grasping of the female by the male’s right geniculate antennule to the separation of the pair, lasted about 2 min. Spermatophore placement started at about 30 s to 1 min after mating began and took approximately 1 min. Immediately after the spermatophore had been fixed in the female’s genital segment, the pair separated.3. The total oviducal cycle, including the gravid phase where the female carried ripe oocytes and the non-gravid phase where the female did not carry ripe oocytes, lasted about 5–6 days. The non-gravid phase was particularly long; it was longer than the gravid phase and constituted 62–72% of the total cycle.4. Mating and spermatophore placement usually occurred with gravid females although occasionally (in 30 of 200 observations) spermatophores were attached in the genital segment of non-gravid females. Generally two to four, but up to seven, spermatophores were observed at a female’s genital segment at the same time.5. Clutch size, rate of egg production and adult longevity depended on food. When fed on C. reinhardtii, females carried 7–8 eggs clutch−1, produced a mean of 1.3 clutches and lived 14 days on average. When fed natural mixed food, females carried 10 eggs clutch−1, produced 5.6 clutches and lived 37 days on average.6. Removal of males after the first clutch resulted in no further egg production. Re-mating is necessary in E. gracilis for continuous clutch production and the production of fertile eggs.7. Mating duration is comparatively short and the non-gravid phase comparatively long in E. gracilis. This could be an adaption to the life in the pelagic zone of the lake, where fish predators are present. Fish select ovigerous females, pairs in copula and, probably, females with ripe oocytes which make them conspicuous. Thus, a short mating duration and a prolonged period without conspicuous oocytes, can be advantageous.
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